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Access to adequate and secure sanitation to prevent and reduce disease occurrence and improve people's health has been a longstanding global concern. Toilet standardization is immensely important for the promotion of sanitation in China. At present, China has more than 200 toilet-related standards, including national, industrial, provincial, association, and enterprise standards. In addition, there are many existing problems with the standard system, such as standards lagging, standards deficiency, and cross-repetition of standards content. This study analyzed the toilet standards utilizing a six-dimensional structure of the standardized system engineering methodology. A framework for the toilet standard system, which consists of six components, is proposed: basic general standard, public toilet standard, household toilet standard, toilet hardware standard, environmental health and safety standard, and toilet accessory standard and standard toilet peripherals. Additionally, the study suggests approaches for improving standardization including cultivating and developing association and enterprise standards, establishing a standardization technical committee, strengthening standard publicizing and implementation, and linkages with international standards. HIGHLIGHTS A six-level framework of the toilet standard system in China is presented and elaborated.; Problems and potential barriers for toilet standardization in China are analyzed.; We suggest establishing a technical standardization committee, standardization organization coordination mechanism, etc. to promote toilet standardization.; This study provides insights that will guide the formation of effective policies and strategies to enhance sanitation in China.;

In this study, a black-shading cylindrical water tank made of high-density polyethylene was locally manufactured as a household digestor for treating cow manure in Bangladesh. Effluent slurry instead of water was reused for manure dilution under manure-to-slurry ratios of 1:2 and 1:1, to assess this small prototype’s production efficiency and feasibility. The specific biogas production at both ratios matched well, by 0.12 m3/kg VS and 0.14 m3/kg VS, respectively, while the former slurry dilution operation outperformed in daily and accumulative biogas production by 16% and 57%, correspondingly, referring to 0.49 Nm3/d on average and 8.55 Nm3 in total, potentially meeting a 2 h household cooking energy requirement. From a nationwide viewpoint, slurry dilution was proven to be a great initiative to conserve water amounting to 50,286,751 m3 for 114,810 households of 6 person-equivalents annually, while cutting chemical costs by USD 32,720,684/yr and trimming annual greenhouse gas emission by 1.8 million tons of CO2e. This study revealed that a small prototype digestor could be an alternative energy source for cost-effective and eco-friendly household applications.

Nutrient recovery and recycling are of great importance in sustainable development. Blackwater (BW) refers to wastewater from toilets, which contains feces, urine, water, and toilet paper from flush toilets. The highly concentrated nutrients of blackwater could be collected through source separation and treated adequately to recover nutrients efficiently and economically. The review intends to give an overview of the characteristics of BW and different techniques to recover nutrients and other valuable products. A number of these technologies are currently under development or being tested at laboratory or pilot scale. The perspective for blackwater nutrient recovery technologies is very positive due to their great potential. For application of source-oriented sanitation infrastructure and systems, there is still a long way to go for development of commercial technologies and valuable products.

More than 500 million people will be added to Africa’s cities by 2040, marking the largest urbanization in history. However, nonrenewable fossil energy sources are inadequate to meet Africa’s energy needs, and their overexploitation leads to intensified global warming. Fortunately, Africa has a huge potential for biomass energy, which will be an important option for combating climate change and energy shortage. In this study, we present a typical large-scale biogas plant in Burkina Faso, West Africa (Ouagadougou Biogas Plant, OUA), which is the first large-scale biogas generation plant in West Africa. The primary objective of OUA is to treat human feces, and it serves as a demonstration plant for generating electricity for feed-in tariffs. The objectives of this study are to assess the greenhouse gas reduction capacity and economic, environmental, and social benefits of OUA and to analyze the opportunities and challenges of developing biogas projects in Africa. As a result, the net economic profit of the OUA biogas plant is approximately USD 305,000 per year, with an anticipated static payback period of 14.5 years. The OUA plant has the capacity to treat 140,000 tons of human feces and 3000 tons of seasonal mixed organic waste annually, effectively reducing greenhouse gas emissions by 5232.61 tCO2eq, improving the habitat, and providing over 30 local jobs. Finally, the development of biogas projects in Africa includes advantages such as suitable natural conditions, the need for social development, and domestic and international support, as well as challenges in terms of national policies, insufficient funding, technical maintenance, and social culture.

The implementation of the United Nations (UN) Millennium Development Goals (MDGs) and Sustainable Development Goals (SDGs) has resulted in an increased focus on developing innovative, sustainable sanitation techniques to address the demand for adequate and equitable sanitation in low-income areas. We examined the background, current situation, challenges, and perspectives of global sanitation. We used bibliometric analysis and word cluster analysis to evaluate sanitation research from 1992 to 2016 based on the Science Citation Index EXPANDED (SCI-EXPANDED) and Social Sciences Citation Index (SSCI) databases. Our results show that sanitation is a comprehensive field connected with multiple categories, and the increasing number of publications reflects a strong interest in this research area. Most of the research took place in developed countries, especially the USA, although sanitation problems are more serious in developing countries. Innovations in sanitation techniques may keep susceptible populations from contracting diseases caused by various kinds of contaminants and microorganisms. Hence, the hygienization of human excreta, resource recovery, and removal of micro-pollutants from excreta can serve as effective sustainable solutions. Commercialized technologies, like composting, anaerobic digestion, and storage, are reliable but still face challenges in addressing the links between the political, social, institutional, cultural, and educational aspects of sanitation. Innovative technologies, such as Microbial Fuel Cells (MFCs), Microbial Electrolysis Cells (MECs), and struvite precipitation, are at the TRL (Technology readiness levels) 8 level, meaning that they qualify as “actual systems completed and qualified through test and demonstration.” Solutions that take into consideration economic feasibility and all the different aspects of sanitation are required. There is an urgent demand for holistic solutions considering government support, social acceptability, as well as technological reliability that can be effectively adapted to local conditions. Keywords: Sanitation, Bibliometric analysis, Research hotspots, Gaps, Challenges

Human urine is a source of fertilizer and, with proper management, it can be reused in agriculture. Determining the contamination issue of antibiotics in source-separated urine is important because the majority of antibiotics are excreted with urine. In this study, source-separated urine samples were randomly collected from a male toilet in a university building and analyzed in terms of 30 typical antibiotics (including 14 sulfonamides, 4 tetracyclines, and 12 fluoroquinolones) and tetracycline-resistant Escherichia coli, as well as its antibiotic-resistant genes to determine the contamination characteristics of antibiotic-related pollution in fresh and stored urine. Results showed that 18 out of 30 typical antibiotics were detected in fresh source-separated human urine. The dominant antibiotic was oxytetracycline with a frequency of 100%, followed by tetracycline, sparfloxacin, enrofloxacin, and ofloxacin, which demonstrated a detection frequency of 55%. Among the detected values, sulfonamides (2 antibiotics), tetracyclines (4 antibiotics), and fluoroquinolones (12 antibiotics) had a concentration range of 0.25–2.94, 0.94–41.2, and 0.06–163.16 ng/mL, respectively. Furthermore, tetracycline-resistant Escherichia coli, which was measured using plate count method, and its related gene, tet M, exhibited a maximum cell density of (200,000 ± 5000) CFU/100 mL and (2.73 ± 0.261) × 107 copies/mL, respectively. When the fresh urine was stored in an ambient environment for 30 days to simulate the real circumstances of urine management, a significant reduction in antibiotics and antibiotic-resistant bacteria was observed, while the change in antibiotic-resistant genes was insignificant. The results of this study suggest that risks associated with antibiotics and their antibiotic-resistant bacteria and genes are retained during collection and storage. Hence, these kinds of microcontaminants must be considered in further urine utilization.

Every day, human beings produce excreta all over the world, and the sludge that accumulates in waste disposal systems is referred to as the 'faecal sludge (FS)'. FS can cause serious environmental pollution in urban areas if it cannot be disposed of properly. A complete FS management system must include onsite sanitation technologies, FS collection and transport, a treatment plant, and resource recovery or disposal of the treatment end-products. Focusing on the treatment and reuse/disposal step of a FS complete service chain, this research presents two cases of FS treatment in Beijing. In Case 1, FS biogas plant adopts anaerobic digestion (AD) to treat FS, and the digestate can be used as biofertilizer in the surrounding greenhouse. In Case 2, several technologies including solid-liquid separation, dewatering, pyrolysis, AD and co-composting are integrated to find innovative solutions for FS treatment. A comprehensive assessment including the aspects of technology, economy and environment is conducted for further SWOT (Strengths, Weaknesses, Opportunities and Threats) analysis. Then, critical strategies are developed, which include (1) selecting project site for optimized transportation, maximum waste reuse, minimum environmental impact and convenient final effluent disposal; (2) planning technical options at a feasible study stage, considering resource recovery, secondary pollution prevention and fire protection; (3) exploring market channels for by-products sale to increase profitability; (4) guaranteeing engineering quality and service life for the purpose of sustainable operation; (5) minimizing health risks to persons exposed to the untreated FS; and (6) providing necessary training for hygiene protection. The cases in Beijing can provide valuable lessons for urban areas in developing countries and the strategies can provide a reference for stakeholders and decision-makers who intend to develop FS treatment projects. [ABSTRACT FROM AUTHOR]